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<h3 class="section" id="Inter_002dprocedural-optimization-passes"><span>9.4 Inter-procedural optimization passes<a class="copiable-link" href="#Inter_002dprocedural-optimization-passes"> &para;</a></span></h3>
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<p>The inter-procedural optimization (IPA) passes use call graph
information to perform transformations across function boundaries.
IPA is a critical part of link-time optimization (LTO) and
whole-program (WHOPR) optimization, and these passes are structured
with the needs of LTO and WHOPR in mind by dividing their operations
into stages.  For detailed discussion of the LTO/WHOPR IPA pass stages
and interfaces, see <a class="ref" href="IPA.html">Using summary information in IPA passes</a>.
</p>
<p>The following briefly describes the inter-procedural optimization (IPA)
passes, which are split into small IPA passes, regular IPA passes,
and late IPA passes, according to the LTO/WHOPR processing model.
</p>

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<li><a href="Small-IPA-passes.html" accesskey="1">Small IPA passes</a></li>
<li><a href="Regular-IPA-passes.html" accesskey="2">Regular IPA passes</a></li>
<li><a href="Late-IPA-passes.html" accesskey="3">Late IPA passes</a></li>
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